title: New evidence for presence of tyrosinase in substantia nigra, forebrain and midbrain.
abstract: Tyrosinase and tyrosinase-related proteins (TRP-1 and TRP-2) are essential for melanin synthesis and are expressed in neural crest-derived melanocytes and in the pigment epithelium of the retina. Recent results suggest expression of all three proteins within the central nervous system. We performed a transgenic assay using beta-galactosidase as reporter gene to monitor tyrosinase promoter activity in vivo. During embryogenesis, we found expression in several locations of developing forebrain and midbrain. Tyrosinase, TRP-1 and TRP-2 had been equally found in extracts of adult mouse brain. In adult brain, we detected tyrosinase promoter activity in cortex, olfactory system, hippocampus, epithalamus and substantia nigra, areas corresponding to positive staining during embryogenesis. Thus, tyrosinase promoter is active throughout murine brain development, and tyrosinase could be implicated in neuromelanin formation in the substantia nigra, and in neurodegenerative disorders like Parkinson's disease.
authors.affiliation: Swiss Institute for Experimental Cancer Research (ISREC), Chemin des Boveresses 155, CH-1066 Epalinges, Switzerland.
authors.forename: K
authors.initials: K
authors.lastname: Tief
authors.forename: A
authors.initials: A
authors.lastname: Schmidt
authors.forename: F
authors.initials: F
authors.lastname: Beermann
mesh_terms: D000818:Animals; D001921:Brain / Q000254:growth & development / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D019746:Intramolecular Oxidoreductases / Q000032:analysis / Q000096:biosynthesis*; D008562:Membrane Glycoproteins; D008636:Mesencephalon / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D014442:Monophenol Monooxygenase / Q000032:analysis / Q000096:biosynthesis*; D009928:Organ Specificity; D010088:Oxidoreductases; D011401:Promoter Regions, Genetic; D016548:Prosencephalon / Q000378:metabolism*; D014176:Protein Biosynthesis; D011506:Proteins / Q000032:analysis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D013378:Substantia Nigra / Q000378:metabolism*; D001616:beta-Galactosidase / Q000096:biosynthesis
chemical_list: D008562:Membrane Glycoproteins; D011506:Proteins; D011993:Recombinant Fusion Proteins; D010088:Oxidoreductases; C079621:Tyrp1 protein, mouse; C064056:tyrosinase-related protein-1; D014442:Monophenol Monooxygenase; D001616:beta-Galactosidase; D019746:Intramolecular Oxidoreductases; C042501:dopachrome isomerase